I hear often the negative form “c’est pas ma tasse de thé” in France but almost never the affirmative “c’est ma tasse de thé” .

“C’est mon truc” works in both affirmative and negative forms.

The familiar “c’est (pas) mon délire” works as well in circles of young friends.

Another familiar expression is “c’est (pas) mon dada”, which is older. It works in negative form but is mostly used affirmatively.

If you are looking for a positive sentence, expressing someone’s affect for an idea, object or situation, the expression “ça me botte !” may suit you.

It comes from the word “Botte”, French translation of the word boot. You feel comfortable in the boot, it suits you, it becomes your boot, not because you wear the boot, but because the boot “wears you” as it was designed for your foot.

It may be too close of the expression “Comme un gant” (like a glove), because of the idea of a physical fit but it can be relevant depending on the context.